Means for providing suction for operating power actuators



1927' c. s. BRAGG ET AL MEANS FOR PROVIDING SUCTION FOR OPERATING POWER ACTUATORS Filed NOV- 25, 1925 Patented Aug. 23, 19 7- UNITED. STATES PATENT OFFICE.

CALEB s. BRAGG, or ram; BnAcm rLomnA, AND vrc'roa w. KLIESBATH, or river WASHINGTON, NEW YORK, ASSIGNORS TO BBAGG-KLIESBATH CORPORATION, 0] LONG ISLAND CITY, NEW YORK, A CORPORATION OF NEW YORK.

IEANS FOR PROVE-DING SUCTION FOR OPE RATING POWE B ACTUATORS.

Application filed liovemberali, 1925. .Berial No. 71,270.

Our invention consists in the novel features hereinafter described, reference be ng had to the accompanying drawlng, whic illustrates one form in which we "have contemplated embodying the invention and carrying it into effect, and'the said invention is fully disclosed in the following description'and claims. 1

Our invention relates to a new method of, and apparatus for, operating a power 210-- tuator or servo motor in which differential pressures are obtained by means of a partial vacuum operating on one face of the piston, and atmospheric air, or other hi her pressure fluid operating on the other ace of the piston, suction for producing the desired rarefication or partial vacuum being obtained from an internal combustion engine.

Our invention is particularly applicable to the operation of power actuators employed in connection with automotive vs-- hicles operating on land, on or in water, or

in the air, and especially for the operation of vacuum brake mechanism for automotive land vehicles. In the operation of such power actuators, it has been customary to obtain the necessary suction or rarefication by means of a, pipe connection to the suction passage of the internal combustion engine of the vehicle, between the throttle valve and the engine cylinders, and usually by tapping the intake manifold of the engine. As the operation of the internal combustion engine depends upon its-receiving a proper supply of explosive mixture, composed of air and fuel, ordinarily liquid hydrocarbon fuel, in accurate proportions, usually deter- .mined by thecareful adjustment of the carburetor needle valve, it necessarily follows that the withdrawal of any large quantities of atmospheric air from a power actuator and its discharge into the explosive mixture passing through the manifold to theseveral cylinders of a multi-cylinder engine, will'of necessity reduce the degree of rarefication in the manifold or other portion of the suction passage with which it, is connected, and interfere with the operation of the engine, either by unduly diluting the explosive mixture with air, or by so reducing the degree of rarefication in the manifold that proper quantities of fuel will not be drawn in from the carburetor. In either case, the operation of the engine will be interfered with maator depends, it being understood that the F rareficationin the manifold incifiases as the throttle valve is closed.

The object of our invention is to utilize the suction produced by the suction stroke or strokes of the piston or pistons of the internal combustion engine for the operation, of a power actuator, without connectin the power actuator with the intake manifol and without connecting it to any part of the suction passage between the carburetor or the throttle valve and the engine cylinders, so that none of the air exhausted from the power actuator will at any time be discharged into the intake manifold or any other portion of the suction passage, delivering charges of explosivematerial to the cylinder or cylinders. and tothis end, we connect the power, actuator to one or more, but less than all of the cylinders of a multicylinder engine, so that air exhausted from the power actuator will be delivered directly into an engine cylinder or cylinders less than all of the engine cylinders, so that even should the operation of such cylinder or cylinders, but less than all of the cylinders of the multi-cylinder engine, as .are directly connected with v the actuator be affected, the remaining cylinders of the engine will secure their normal charges under the control of the throttle valve, and the stalling of the motor while idling will be positively prevented.

In an internal combustion engine of the four cycle type. having four or more cylinders (which is the customary practice in the larger automotive vehicles), there is a continual state of rarefication within the intake manifold whenever the throttle is closed, the rarification being greatest when the throttle is fully closed for idling (that is, when the motor is turning over slowly with the clutch or gears disengaged). The inlet valve of 'a cylinder of the engine opens when the piston is approximately at the top of the stroke preceding the suction stroke, to effect communication between the cylinder and the intake manifold, at which time, when the; motor is idling, the burnt gases of the power stroke should be reduced to approximately atmospheric pressure, but the partial vacuum in the intake manifold tends to with; draw part of the unexpelled burnt gases into the intake manifold,-which gases, with the fresh hydro-carbon mixture, are immediate 1y sucked back into the cylinder as soon as the piston has traveled downward on the suction stroke sufficiently far to create a greater state of rarefication within the cyl-' inder than exists in. the intake manifold.

' manifold by the vacuum created therein bymotor stalling while idling.

We therefore propose to connect the suction pipe from the power actuator. with the cylinder at or just below the point where the vacuum in the cylinder equals or slightly exceeds that in the intake manifold when the -motor'isidling. By so doing, any air exhausted from the power actuator will be sucked into the cylinder by the vacuum created in that cylinder, but will not be sucked through the open inlet valve into the intake all cylinders, as'would be the case were this pipe connected to the explosion chamber of the cylinder. As the capacity of one, two, or lessthan all the cylinders of a motor, as

for example a four-cylinder, a six-cylinder or an eight-cylinder motor, would be more than ample to operate any power actuator plosive mixture are not in any way diluted or affected, will continue to function normally, so that there will be no danger of the It follows, therefore, that by our present invention the use of restricting means in the suction pipe leading from the powe actuator to the engine, may be dispensedwith, and the instantaneous and unretarded operation of the actuator, with full powerand efiiciency, is at all times insured gi t Obviously, an automatic check valve must be inserted in the suction "pipe adjacent to the engine cylinder in order to prevent the gases produced by the explosion of the charges from passing through the suction pipe into the power actuator. This valve, however, being located a considerable distance, from the head of the engine cylinder,

as for example a distance therefrom substantially equal to half the stroke of the piston, such valve or valves will not be exposed to the highest heat nor to the highest pressure resulting from the explosion of the explosive charges, but are only submitted to relatively low pressures and temperatures, and will, therefore, function Without difficulty.

In the accompanying drawings, we have ilwith the lustrated one arrangement for carrying-our invention into efiect, in which Fig. 1 represents a diagrammatic new of an installation in an automotive vehicle for use on land, of a power actuator opera-.

tively connected with the brake mechanism 'of the vehicle and having its suction pipe' connected to two cylinders of a six-cylinder internal combustion engine, for example.

Fig. 2 is an enlar ed sectional view representing a cylinder 0 the engine to which the suction pipe is connected and showing the check valve locatedtherein.

Fig. 3 is a sectional view of one form of suction actuated device or power actuator,

indicated in Fig. 1, which we may employ in 'which may be of any particular type, and

while only one brake mechanism is actually shown in Fig. 1, it is to be understood that any desired number of the wheels of the vehicle may be rovided with brake mechanism simultaneous y actuated. In this instance,

ers and receiving the exthe brake mechanism shown is provided with an operating lever, 72.

1, represents the cylinder of a power actuator, provided with a piston, 3, adapted to be moved in a: direction to apply the brakes by atmospheric air (or other higher pressure fluid) acting on the rear face of the iston, a partial vacuum-being produced 1n the cylinder forward of the piston, as hereinafter described, suitable controlling valve 1 mechanism being provided for controllin the actuator. The piston, 3, is provide piston rod 5, connected by a link, 73, with t e operating lever, 72, of the brake mechanism (or 'm'echanisms). In this instance, the valve mechanism shown, which is indicated at 40, 41 is located within-the hub of the piston, and is of the construction shown and described and claimed in our former Patent. No. 1,583,117, granted May 4, 1926, but it is to be understood that the particular form of actuator and the particular form of valve mechanism for controlling the same, form no part of our present invention and will not be specifically described or claimed herein.

In this instance, the cylinder on the forward side of the piston is directly connected 85. A forward movement of the foot lever operating the valve mechanism will bring about a forward movement of the iston to apply the brakes; and vice versa, t e return movement of the foot lever will bring about the return movement of the piston and release the brake mechanism.

The suction pipe, 62, is shown in this in stance as connected to'two of the cylinders only, 60 and 60", of the engine, and as indicated in Fig. 2, the connection of the pipe,

, 62, to the cylinder, is at a point approximately midway of the stroke of the piston, so that when the piston is at the top of its stroke, the communicating pipe, 62, will be closed by the piston- The suction, pipe, 62, is also provided adjacent to each cylinder with which it is connected, with a check valve, 66, normally held in seated position, in this instance by a spring, 67 so that when the cylinder ort, ind1cated at 62, communicating with t e suction ipe, 62, is uncovered by the piston during til the burnt gases of combustion will not forced through the-suction pipe, 62, into the actuator. 68, in Fi 2, represents, more or less diagrammatical y the inlet valve for controlling the admission of explosive mixture from the intake manifold, 61, into the cylinder, and each cylinder will of course.v

- be provided with the usual exhaust port and exhaust valve (not shown), as is customary in internal combustion engines. When the engine is operatin idly, with the throttle closed, or partly c osed, there will be a certain amount of rarefication in the manifold, 61, so that as the engine piston indicated at 59, rises on the exhaust stroke to expel the burnt gases previous to commencing the suction stroke and passes its highest -position, the inlet valve, 68, will open and as a partial vacuum exists in the manifold, some of the burnt gases will be drawn into the manifold, but as the piston descends on its suction stroke, these burnt gases will be drawn back into the cylinder together with a freshcharge of explosive mixture, as soon as the downward movement of the iston effects rarefication within the cy inder neaaere e power stroke fol-v lowing the ignition of an explosive char possibility can any air be withdrawn from the actuator into the intake manifold, and therefore the ex losive charges will be furnished to the otli with which the suction pipe, 62, is not connected, without any dilution or other interferenc'e from the power actuator. When the iston has descended to or slightly beyond the point where the suction within the cylinder, 60, for example (as shown in Fig.- 2) is greater than that in the manifold, the communicatin aperture, 62", which communicates wit the suction pi e, 62, will be uncovered b the piston an air will be withdrawn om the suction pipe, 62, and

er cylinders of the engine from the actuator cylinder, if there 'is any air therein, at the same time that a partial charge of ex losive mixture is drawn into the cylinder fi'om the-intake manifold. The valve, 66, in the suction ipe, 62, opens to permlt' the withdrawal 0 air through. the suction pipe, 62, into the cylinder, during the suction stroke, whenever there is suflicient air at higher pressure to overcome thelight spring, 6

In practice, we prefer to so arrange the controlling valve mechanism that the portion of the actuator cylinder forward of the piston is maintained in a larified condition of partialvacuum, and we may also so construct the valve mechanism as to maintain an equal state of partial vacuum on both faces of the piston, as set forth in our former application above referred to, in order that on the admission of atmospheric air or other higher pressure fluid'in rear of the piston, an instantaneous operation of the brake mechanism may be effected. The combination of this form of actuator as herein shown with a'suction pipe leading to one, or a small minority of. the cylinders in the manner described, enables us to obtain ad-- ditional advantages. The suction by one or this small number of c inders is of course greatly less than that w ich could be obtained by connecting the suction pipe with the manifold which would be sub'ect to the suction from all the cylinders w en the-throttle is closed, and therefore where the forward end of the actuator cylinder is not maintained in a state of rarefication it lproduced will require a certain amount of time for the single cylinder, or few cylinders connected with the actuator, to exhaust the air from the actuator and apply the brakes, and this might delay the application of the brakes in some cases. Where, as herein shown, the forward end of the cylinder and in some instances both ends of the cylinder) are maintained in a state of rarefication, the air is exhausted between operations of the actuator when it is not in operation, and when the actuator is operated, it is only necessary to admit air in rear of the piston to secure an instantaneous response 0 the acsibility of stalling, if idling, and destroying the source of "suction upon which the operation of the actuator depends. But this is not essential and if the controlling valve mechaz. nism is operating at any tiriieand under any condition so as to connect the suction pipe,

62, with the cylinder forward of the plston and admit atmospheric air or other higher pressure fluid in rear of the piston, the suction of the cylinders as and 60", less than the whole number oi cylinders in the engine,

' with which the suction pipe, 62, is connected,

will be'sufficient to exhaust the air from the cylinder forward of the piston and permit the atmospheric air or higher pressure fluid to move the piston forward in a direction to apply the brakes, and it will be understood that when the valvemechanism is reversed, the suction of the cylinder connected with the pipe, 62, will exhaust from the actuator cylinder the air admitted to effect the power stroke of the actuator piston and insure the release of the brake mechanism, either by permitting it to release itself (or by admitting atmosphericair or higher pressure fluid to the cylinder forward of the piston, to

positively return the parts to their normalposition In any case, any air admitted to the ac tuator cylinder for the purpose of actuating the pistorrtherein, will be withdrawn through the suction pipe, 62, into the cylinders of the engine connected therewith, under the control of the-reversing valve mechanism. This may temporarily dilute the explosive charges received by these cylinders to such an extent as to cause them to miss stalling if idling, and without any interruption of the suction upon which the operation of the actuator depends. It Wlll be understood that should the cylinder or cylinders with which the actuator suction pipe is connected miss fire, by reason of the dilution of its charge by the air drawn in from the acituator, this will only occur occasionally and for a limited number of strokes of the pistons in such cylinders, and will not materially afiect the running ofthe engine, while the necessary suction to effect the instantaneous operation of the actuator and the brake mechanism or other device) connected therewith, with the full power of the actuator, will be assured at all times when the actuator is called into operation by the operation of itscontrolling valve mechanism. We

do not desire to be limited to exact location of the aperture in the cylinder with which the suction pipe leading to the Vacuum or suction actuator is connected. We prefer to locate it at such a distance below the position occupied by the head of the piston, when in its highest position, that when said aperture is opened by the downward movement of the piston on the suction stroke, the degree of rarelication within the cylinder shall be at least as great or greater than the degree of rarefication existing in the manifold, with the object that no air drawn through the suction pipe at any time shall be permitted to pass into the intake manifold and atfeet the normal charges of combustible mixture passing to the other cylinders of'the engine not connected with the suction-pipe.

It will be noted that thesuction pipe COD, nects. the actuator directly with a cylinder, or cylinders of the engine independently of the means for supplying the normal ex 10- sive chargesthereto, delivering the air withdrawn vfrom the actuator into the portion of the cylinder subject to variations of pres sure by the movements of the piston, and the word directly in the followin claims is used with that :meanin It w ll also be noted that by locating t e port, 6%, in the side of the engine cylinder in the position shown, it is closed by thepiston durin the first portion of the explosion stroke 0 the piston, thereby protecting the port from being closed by carbon.

What we claim and desire to secure by Letters Patent is:

l. The combination with an internal combustion engine of the four cycle type, ,provided with a, suction passage for supplying explosive charges to the engine, of a suction actuated device comprising a cylinder, a piston therein, and controlling valve mecha nism, and asuction pipe extending from the 'cylinder of the suction actuated device and connected to a cylinder of the engine adjacent to the position of thepiston head there ingihenc said "'piston has moved far enough "(i1 its suction stroke' 'to produce rarefication within the cylinder greater than that existingkin the charge supplying suction passage.

2; The combination with an internal combustion engine of the four cycle type, pro vided with a suction passage for supplying explosive charges to the engine, of a suction actuated device comprising a cylinder, a piston therein, and controlling valve mechanism, and a suction pipe extending from the cylinder of the suction actuated device and connected to a cylinder of the engine adjacent to the position of the piston head therein, when said piston has moved far enough on its suction stroke to produce rarefication within the cylinder greaterthan that existing in the charge supplying suction passage,

and a check valve interposed between the v prising a cylinder, a piston therein, and con- 10 trolling va ve mechanism, means for connectmg the cylinder of said suction actuated device with certain cylinders of the engine less than the whole number, at points ad acent to the position of the piston head therein, when the piston has moved far enough on its suction stroke to efi'ect a rarefication within the cylinder greater than that in the charge sup-' plying suction assage, and a check valve for each cylin er, soconnected with the suction actuated cylinder-as to prevent the passage of gases of explosion to the cylinder of said suction actuated device.

4. In an automotive vehicle, the combination with a multi-cylinder internal combustion engine of the four cycle ty e, for propellin the vehicle, brake mec anism for the vehicle, of a suction actuated power actuator comprising a cylinder, a piston therein, .operatively connected with the brake mechanism, and controlling valve mechanism, and a suction ipe for the actuator cylinder connected wit certain cylinders of the engine less than the whole number, at a. point with respect to each, adjacent'to the.

position of the head of the piston therein, when thepiston has moved on its suction stroke far enough to .efiect a rarefication within the cylinder greater than that in the charge supplying suction passage.

5. The combination with an internal combustion engine of the four cycle type, protrol of the said valve mechanism, to a cylinder of the engine and connected to said cylinder by a port located in the side of the cylinder and adapted to be closed by the engine piston therein during the explosion stroke, until said piston-has completed more than half of the travel of the explosion stroke suction pipe.

suction actuated device comprisin whereby the said port will be protected from being closed by carbon, and a check valve interposed between said cylinder 6. The combination with an internal combvstion engine of the four cycle type, of a der, a'piston therein, and control mg valve mechanism, and a suction pipe extending from the suction actuated device anddirectly connected to a cylinder of the engine.

7 The combination with a multi-cylinder internal combustion engine of the four cycle type provided with means for supplying the' normal explosive charges to said cylinders, of a suction actuated device comprising a cylinder and piston and controlling valve mechanism, an a suction pipe extending from the suction actuated device and connected directly. to certain of the engine cylinders less than the whole number, whereby the withdrawal of air in the operation of the suction actuated device will not affect the ex losive charges delivered to the other cylin' ers of the engine.

8. The combination with a'multi-cylinder internal combustion engine of the four cycle ports and the j a cylintype provided with means for suppilying the normal explosivecharges to said cy nders, of a suction actuated device and means for delivering air from said suction actuated device directly to the workingchamber of'a cylinder of saiden 'ne independentl of the valve mechanism 0 the engine which normally controls the supply of explosive charges to the cylinders, said means operating on the suction stroke of the piston in said cylinder. 9. The combination with a multi-cylinder internal combustion engine of the four cycle t pe, of a suction actuated device, means for, elivering air from, said suction actuated device directly to the working chamber of a cylinder of the engine independently of the valve mechanism of the engine which normally controls the supply of explosive charges to'the cylinders, said meansoperating. upon the suction-stroke ofthe piston in said cylinder and means for preventing the delivery of gaseous material-from said cylinder to the suction actuated device.

In testimony whereof we aflix our signatures.

CALEB S. BRAGG. VICTOR W. KLIESRATH. 

